Information processing device and consumption power control method

ABSTRACT

Information processing equipment is so constructed that the power consumption of a disk drive for hard disks, optical disks, or the like can be reliably and sufficiently reduced. The host CPU ( 120 ) of an information processing unit ( 100 ) forms a command for changing the power consumption mode of a HDD ( 200 ) based on the state of control on the HDD ( 200 ). The host CPU supplies the command to the HDD ( 200 ) through a media controller ( 106 ). When the HDD ( 200 ) accepts the command, it changes its power consumption mode according to the instruction from the information processing unit. Thus, the information processing unit can control the power consumption mode of the HDD ( 200 ) based on the state of control on the HDD ( 200 ).

TECHNICAL FIELD

The present invention relates to information processing equipment thatuses a hard disk, an optical disk, or the like, for example, as arecording medium and a power consumption control method therefor.

BACKGROUND ART

Disk units, such as hard disk drives and DVD drives (Digital VersatileDisk drives), are used for auxiliary information storage devices forpersonal computers, for example. These disk units have a plurality ofpower consumption modes and are so constructed that the powerconsumption mode is changed and controlled on the disk unit side andreduction of power consumption is thereby accomplished.

More specific description will be given. In hard disk drives (hereafter,abbreviated to “HDD”) connected with a personal computer through the ATAttachment (hereafter, abbreviated to “ATA”) interface, for example,power consumption control (power save control) is carried out throughthe functions described below: Standby Timer function, Advanced PowerManagement (hereafter, abbreviated to “APM”) function, or the like.

In this case, a plurality of power consumption modes are provided aschangeable power consumption modes. Such power consumption modesinclude, for example, Active mode, Idle mode that is divided into aplurality of stages, Standby mode, and Sleep mode in descending order ofpower consumption.

The Standby Timer function is for performing the following operation: atime-out value preset by a host device is taken as the initial value;when there is no access from the host device in so-called Idle mode,counting down is started for the time-out value; when the count iszeroed, the mode automatically shifts to Standby mode.

The APM function is for performing the following operation: the HDDitself estimates the pattern of access from the host device to the HDDbased on historical information about accessing from the host device;the power consumption mode is changed based on the result of thisestimation. In this case, the time taken until the power consumptionmode is changed (transition time) is adaptively varied based on thepattern of access from the host device to the HDD.

Various techniques have been disclosed with respect to such powerconsumption control. For example, Japanese Unexamined Patent PublicationNo. Hei 9(1997)-6465 discloses the following technique: informationprocessing equipment is provided with a power saving timer, and thevalue on this power saving timer is adaptively varied. Thus, the powerconsumption is efficiently reduced without degrading the processingefficiency of the information processing equipment.

More specific description will be given. In the technique described inJapanese Unexamined Patent Publication No. Hei 9(1997)-6465, thefollowing operation is performed: in information processing equipmentprovided with a power saving timer, the mode is caused to transition topower saving mode when a time set on the power saving timer has passedafter the last processing operation. When a task resumption requestcomes relatively soon after power saving mode is established in thiscase, the power saving timer is set to a slightly larger value for thenext and following operations. Thus, the mode is prevented fromunnecessarily transitioning to power saving mode.

If the time from when power saving mode is established to when a taskresumption request is made is long, the power saving timer is set to aslightly smaller value for the next and following operations. Thus, themode is caused to transition to power saving mode as quickly aspossible. As mentioned above, Japanese Unexamined Patent Publication No.Hei 9(1997)-6465 describes a technique for estimating the subsequentaccess patterns from access history and changing the mode as in theabove-mentioned APM function of HDDs.

However, the above-mentioned APM function of HDDs and the techniquedescribed in Japanese Unexamined Patent Publication No. Hei 9(1997)-6465have their limit on the accuracy of estimation. This is because, inthese function and technique, access patterns are estimated based on thehistory of access to the device itself that estimates access patterns.For this reason, it is suspected that there are cases where the mode maybe caused to transition to a mode with low power consumption;nevertheless, the equipment stands by in high-power consumption mode,such as Active mode, in which much power is consumed.

It is suspected that there are converse cases where it is likely thataccess immediately takes place; nevertheless, the mode transitions fromActive mode, in which operation can be immediately started, to Idle modeor Standby mode, which takes longer time to start as compared withActive mode.

In these cases, wasteful power consumption occurs, and further loss canbe produced in processing time by an amount equivalent to the time ittakes to transition from Idle mode or Standby mode to Active mode.

Recently, consideration has been given to utilization of hard disk orDVD as a recording medium for so-called mobile devices, such as digitalvideo cameras, which are carried about when used. That is, considerationhas been given to mounting a HDD or DVD drive in the enclosure of amobile device, such as a digital video camera.

In case of mobile device, a battery is used as the power source, and thefollowing requirements must be sufficiently met: lengthening the batteryduration, suppressing temperature rise in the enclosure of the mobiledevice, and the like. However, a problem arises when a HDD or a DVDdrive is mounted in a mobile device. These drives are higher in powerconsumption and produces more heat as compared with the other devicesand components mounted in the same enclosure. For this reason, it isdesirable that the power consumption should be reliably and sufficientlyreduced with respect to various drives, such as HDDs and DVD drives.

The present invention has been made in light of the foregoing. An objectof the present invention is to provide an apparatus and a method whereinthe power consumption of a disk drive for hard disk and optical disk,for example, can be reliably and sufficiently reduced.

DISCLOSURE OF THE INVENTION

In order to solve the above problem, information processing equipmentaccording to the present invention comprises:

the information processing equipment comprises:

an information storing means that records or reproduces data accordingto a plurality of power consumption modes; and an information processingmeans that controls the information storing means with respect to atleast recording or reproduction of the data, in which

the information processing means forms command information for changingthe power consumption mode of the information storing means to anintended power consumption mode based on control state, and theinformation storing means changes the power consumption mode of theinformation storing means according to the command information.

In this information processing equipment of the present invention, theinformation processing means forms command information for changing thepower consumption mode of the information storing means according to thestate of control on the information storing means. In the informationstoring means, its own power consumption mode is changed according tothe command information formed in the information processing means.

Conventionally, in a single information storage device, such as a harddisk drive, the power consumption mode is changed by the informationstorage device itself. According to the present invention, the powerconsumption mode can be changed according to command information fromthe information processing means. More specific description will begiven. The information processing means always precisely grasps how theinformation storing means should be accessed. For this reason, theinformation processing means can implement most proper power consumptioncontrol based on the state of control on the information storing means.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram explaining a recording and reproducing deviceto which the present invention is applied.

FIG. 2 is a block diagram explaining an example of the constitution ofthe HDD illustrated in FIG. 1.

FIG. 3 is a drawing explaining the power consumption modes of the HDDillustrated in FIG. 2.

FIG. 4A and FIG. 4B are drawings explaining normal access andconventional intermittent access.

FIG. 5 is a drawing explaining intermittent access made in the recordingand reproducing device illustrated in FIG. 1.

FIG. 6 is a drawing explaining the Set Features command.

FIG. 7 is a drawing explaining the values settable on the Featuresregister under the Set Features command and the meaning of them.

FIG. 8A and FIG. 8B are drawings explaining an concrete example of theSet Features command for controlling enabling/disabling of the DPMfunction.

FIG. 9 is a drawing explaining the Idle Immediate command.

FIG. 10 is a drawing explaining the values settable on the Featureregister under the Idle Immediate command and the meaning of them.

FIG. 11A to FIG. 11D are drawings explaining a concrete example of theIdle Immediate command.

FIG. 12A and FIG. 12B are drawings explaining the Check Power Modecommand.

FIG. 13A and FIG. 13B are drawings explaining the values the SectorCount register under the Check Power Mode command can take and themeaning of them.

FIG. 14 is a drawing explaining the HCAPM function.

FIG. 15 is a drawing explaining the Set Features command utilized to usethe HCAPM function.

FIG. 16 is a drawing explaining the Set Features command utilized to usethe HCAPM function.

FIG. 17 is a drawing explaining the Set Features command utilized to usethe HCAPM function.

FIG. 18 is a drawing explaining the power consumption control functionof the recording and reproducing device illustrated in FIG. 1.

FIG. 19 is a flowchart explaining switching control for the APM functionand the DPM function, carried out in the recording and reproducingdevice illustrated in FIG. 1.

FIG. 20 is a drawing explaining the processing of detecting the powerconsumption mode of the HDD, performed in the recording and reproducingdevice illustrated in FIG. 1.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereafter, description will be given to an embodiment of the presentinvention with reference to drawings. The embodiment will be describedbelow, taking as an example a case where the apparatus and methodaccording to the present invention are applied to the following item: adigital video camera that is a recording and reproducing device providedwith camera functions and incorporating a HDD (Hard Disk Drive) forusing a hard disk as a recording medium.

[Recording and Reproducing Device]

FIG. 1 is a block diagram for explaining a recording and reproducingdevice in this embodiment. As illustrated in FIG. 1, the recording andreproducing device in this embodiment is roughly composed of aninformation processing unit (information processing means) 100 and aninformation storing unit (information storing means) 200, each providedwith a CPU. The information storing unit 200 is a HDD incorporated inthe recording and reproducing device in this embodiment. In thefollowing description, the recording and reproducing device will bedivided into the information processing unit 100 and the informationstoring unit, or the HDD 200. Description will be given to theconstitution and operation of each component.

[Information Processing Unit 100]

First, description will be given to the information processing unit 100of the recording and reproducing device in this embodiment. Asillustrated in FIG. 1, the information processing unit 100 of therecording and reproducing device in this embodiment is provided with thefollowing items as input and output ends for information: digitalinput/output terminal io, digital output terminal out, digital inputterminal in, and camera block 101.

As illustrated in FIG. 1, the information processing unit is alsoprovided with a signal processing system, a monitor output system, and ahost CPU (Central Processing Unit) 120. The signal processing systemcomprises two switch circuits 102 and 104, an encoder/decoder 103, abuffer memory circuit 105, and a media controller 106. The monitoroutput system comprises a controller 108 for output, an LCD (LiquidCrystal Display) 109, and a speaker 110. The host CPU controls eachpart.

As illustrated in FIG. 1, the host CPU 120 is connected with a ROM (ReadOnly Memory) 121, a RAM (Random Access Memory) 122, a nonvolatile memory123, such as EEPROM (Electrically Erasable and Programmable ROM), and isfurther connected with a key operation portion 111.

The key operation portion 111 is for accepting instruction input from auser, and is provided with function keys, including an operation modechange-over key, playback key, stop key, fast forward key, fast reversekey, pause key, and the like, other various adjusting keys, and thelike.

The operation modes of the recording and reproducing device in thisembodiment include, for example, shooting mode and normal mode. Theshooting mode is a mode in which images are picked up through the camerablock 101, and the pictures and sounds picked up are recorded on thehard disk 200A in the HDD 200.

The normal mode is a mode in which operations other than those inshooting mode can be performed. In this mode, the following operationsare performed: information signals recorded on the hard disk 200A in theHDD 200 are read and reproduced; and information signals suppliedthrough the digital input/output terminal io or the digital outputterminal out are recorded on the hard disk 200A in the HDD 200.

The recording and reproducing device in this embodiment can be broughtinto so-called function disabled state by predetermined key operation.In this state, the recording function and reproducing function of therecording and reproducing device in this embodiment are disabled toprevent power from being consumed.

The ROM 121 connected with the host CPU 120 is for storing variousprograms executed at the host CPU 120 and data required for processing,and the RAM 122 is used mainly as a work area. The nonvolatile memory123 is for storing varied setting information and parameters that mustbe held even after the power supply is turned off.

The host CPU 120 performs the operation described below. In response toa request from a user inputted through the key operation portion 111, itcarries out the following controls: control of encoding and decoding ofaudio/visual data (hereafter, referred to as “AV data”) consisting ofaudio data and visual data, buffer control, media controller control,switch control, and the like. Thus, the host CPU makes it possible torecord AV data and the like, supplied to this recording and reproducingdevice, on the hard disk 200A in HDD 200, and read and reproduce the AVdata recorded on the hard disk 200A in the HDD 200.

[Operation of Information Processing Unit 100]

Description will be given to the flow of information signals that takesplace in the information processing unit 100 of the recording andreproducing device in this embodiment when the signals are recorded andreproduced. First, description will be given to the flow of informationsignals that takes place when they are recorded.

[Flow of Information Signal (Data) when Recorded]

The recording and reproducing device in this embodiment is soconstructed that, when shooting mode is established through the keyoperation portion 111, pictures and sounds picked up through the camerablock 101 can be accepted and recorded on the hard disk 200A in the HDD200.

Further, the recording and reproducing device is so constructed that,when normal mode is established through the key operation portion 111and an external digital device, such as a personal computer, isconnected with the digital input/output terminal io, the following takesplace: the recording and reproducing device inputs and outputs datathrough the digital input/output terminal io. Thus, the recording andreproducing device can be used as an auxiliary information storagedevice for an external digital device connected therewith. The digitalinput/output terminal io complies with the USB (Universal Serial Bus)2.0 standard.

Further, the recording and reproducing device is so constructed that,when no external digital device is connected with the digitalinput/output terminal io in normal mode, data can be accepted throughthe digital input terminal in and outputted through the digital outputterminal out.

First, specific description will be given to the flow of signals thattakes place in the following case: shooting mode is establishedaccording to an instruction from a user, accepted through the keyoperation portion 111; and visual data and audio data from the camerablock 101 are recorded.

When shooting mode is selected, the settings of the switch circuit 102and the switch circuit 104 are changed to the input end b side under thecontrol of the host CPU 120, as illustrated in FIG. 1. In the case ofthis example, further, the host CPU 120 accesses the hard disk 200A inthe HDD 200 at a logical address through the media controller 106, andacquires required information, such as management information, formed onthe hard disk 200A. The host CPU 120 obtains required information fromthe acquired management information and the like, and makes preparationsfor recording and grasps free cluster positions.

The camera block 101 comprises a lens, a CCD (Charge Coupled Device), amicrophone, and the like, which are not shown in the figure. The camerablock can convert the image of a subject coming through the lens intovisual signals through the CCD, and convert them into digital visualsignals. Also, the camera block can collect sounds through themicrophone, and convert them into electrical signals. Further, it canconvert them into digital audio signals, and output AV data consistingof these digital signals to the subsequent circuit.

The AV data outputted from the camera block 101 is supplied to theencoder/decoder 103 through the switch circuit 102. The encoder/decoder103 compresses (encodes) the supplied AV data by a predeterminedencoding scheme, for example, the MPEG (Moving Picture Experts Group)scheme. It supplies the encoded AV data to the buffer memory circuit(hereafter, simply referred to as “buffer”) 105 through the switchcircuit 104.

Writing and reading data to and from the buffer 105 are controlled bythe host CPU 120. Therefore, the AV data from the switch circuit 104 iswritten to the buffer 105 under the control of the host CPU 120, and atthe same time, the AV data already written to the buffer 105 is readout. That is, in the recording and reproducing device in thisembodiment, the time base is corrected with respect to AV data using thebuffer 105 between the recording and reproducing device and the harddisk 200A as a recording medium that are asynchronous with each other.

As mentioned above, when the contents data (information signals) to berecorded is real-time data, such as AV data, consisting of moving imageinformation and audio information, such a scheme that, while thecontents data is written to the buffer 105, it is read out is adopted.The AV data is used by so-called FIFO (First In First Out).

The camera block 101 is capable of not only picking up moving images,but also picking up the still-frame image of a subject in response to aninstruction from the user. In case of recording a freeze-frame picture,contents data is all stored in the buffer 105 or the RAM 122 or the likeconnected with the host CPU 120, and then written onto the hard disk200A. Therefore, to record a freeze-frame picture, real-time processingis unnecessary unlike recording of moving images.

The AV data read from the buffer 105 under the read control of the hostCPU 120 is supplied to the HDD 200 through the media controller 106.Then, it is written in sequence into free spaces on the hard disk 200Ain the HDD 200 based on the previously grasped positions of freeclusters.

During recording of information signals, file management information onthe hard disk is periodically updated by the host CPU 120 through themedia controller 106. When recording of AV data is completed as well,file management information and directory entry information are updatedby the host CPU 120 through the media controller 106.

Thus, AV data consisting of moving images and sounds captured throughthe camera block 101 is recorded in free clusters on the hard disk 200Ain HDD 200.

Next, description will be given to cases where information signals, suchas AV data, supplied through the digital input terminal in are recorded.As also mentioned above, if an external digital device is connected withthe digital input/output terminal io in normal mode, the setting of theswitch circuit 102 is changed to the input end a side under the controlof the host CPU 120. Then, input of information signals through thedigital input terminal in is accepted. The digital input terminal in iscapable of accepting not only supply of moving image information butalso that of still-frame image information and the like.

With respect to information signals supplied through the digital inputterminal in, the same operation as in the above-mentioned case where AVsignals from the camera block 101 are recorded on the hard disk 200A isperformed. That is, information signals supplied through the digitalinput terminal in are recorded on the hard disk 200A in the HDD 200through the encoder/decoder 103, switch circuit 104, buffer 105, andmedia controller 106.

When an external digital device, such as a personal computer, isconnected with the digital input/output terminal io through a USB cablein normal mode, the setting of the switch circuit 102 is changed to theinput end a side under the control of the host CPU 120.

Varied digital data supplied through the digital input/output terminalio need not be encoded. Therefore, it is supplied to the buffer 105through the switch circuit 104. Subsequently, it is recorded on the harddisk 200A in the HDD 200 as in the above-mentioned recording ofinformation signals, such as AV data, from the camera block 101 or thedigital input terminal in.

As also mentioned above, the recording and reproducing device in thisembodiment is so constructed that, when an external digital device isconnected with the digital input/output terminal io, it can operate asfollows: it is used as an ordinary external information storage devicefor the external digital device; and it records data, such as AV data,on the hard disk 200A in the HDD 200 in response to a request from theexternal digital device connected with the digital input/output terminalio.

When AV data from the camera block 101 is recorded (in shooting) andwhen AV data supplied through the digital input terminal in is recorded,the supplied AV data is supplied to the controller 108 for monitoroutput. The controller 108 separates the supplied AV data into visualdata and audio data to from visual signals to be supplied to the LCD 109and audio signals to be supplied to the speaker 110. The formed visualsignals and audio signals are supplied to the LCD 109 and the speaker110. Thus, the pictures and sounds being recorded on the hard disk 200Acan be monitored through the LCD 109 and the speaker 110.

[Flow of Information Signal (Data) when Reproduced]

Next, description will be given to the flow of information signals thattakes place when they are reproduced. When reproduction instructinginput from the user is accepted through the key operation portion 111 innormal processing mode, the host CPU 120 accesses the hard disk 200A inthe HDD 200 at a logical address through the media controller 106. Then,it acquires required information formed on the hard disk 200A, includingmanagement information, file system information such as FAT (FileAllocation Table) information, directory entry information, and thelike.

Then, the host CPU 120 displays a list on the LCD 109 through the hostCPU 120 and the controller 108 or performs like operation based on theacquired information, such as directory entry information. The listcontains files that are recorded on the hard disk 200A and can bereproduced. Thus, the host CPU accepts input selecting a file to bereproduced.

When the host CPU 120 accepts input selecting a file to be reproduced,through the key operation portion 111, it grasps the position on thehard disk 200A where the file to be reproduced is recorded, from theacquired directory entry and file system information.

When an external digital device is connected with the digitalinput/output terminal io in normal mode in this embodiment, as alsomentioned above, the setting of the switch circuit 104 is changed to theterminal a side. When no external digital device is connected with thedigital input/output terminal io, the setting of the switch circuit 104is changed to the terminal b side. Needless to add, such a constitutionthat the user selects either the digital input/output terminal io or thedigital output terminal in may be adopted.

Thereafter, the host CPU 120 controls the media controller 106 and readsinformation signals from the target file stored on the hard disk 200A inthe HDD 200. It writes the information signals, which are read out, tothe buffer 105 through the media controller 106.

As also mentioned above, reading and writing data from and to the buffer105 are controlled by the host CPU 120. Data read from the hard disk200A is written, and data already written to the buffer 105 is read out.In reproduction as well as recording, the time base is corrected withrespect to the information signals to be reproduced, using this buffer105.

The information signals read from the buffer 105 are supplied to thedigital input/output terminal io or the encoder/decoder 103 through theswitch circuit 104. That is, with the setting of the switch circuit 104changed to the terminal a side, the information signals read from thehard disk 200A are supplied through the digital input/output terminal ioto an external digital device, such as a personal computer, connectedtherewith.

With the setting of the switch circuit 104 changed to the terminal bside, the information signals read from the buffer 105 are supplied tothe encoder/decoder 103 through the switch circuit 104. They are decodedthere, and AV data or still-frame image information restored to itsoriginal state before encoding is outputted through the digital outputterminal out.

In this case, as also mentioned above, the AV data decoded at theencoder/decoder 103 is also outputted to the controller 108 for monitoroutput. The AV data is separated there into visual data and audio datato form visual signals to be supplied to the LCD 109 and audio signalsto be supplied to the speaker 110. The formed visual signals and audiosignals are supplied to the LCD 109 and the speaker 110.

Thus, a picture corresponding to visual data outputted through thedigital output terminal out is displayed on the LCD 109; a soundcorresponding to audio data outputted through the digital outputterminal out comes out of the speaker 110. Thus, pictures and soundsrespectively corresponding to visual data and audio data; outputtedthrough the digital output terminal out, can be monitored.

Thus, the recording and reproducing device in this embodiment can besupplied with moving image information and the like, record them on thehard disk 200A in the HDD 200, and read and reproduce informationsignals recorded on the hard disk 200A in the HDD 200.

[Information Storing Unit (HDD) 200]

Next, description will be given to the HDD 200, or the informationstoring unit of the recording and reproducing device in this embodiment.As illustrated in FIG. 2, the HDD 200 comprises a connection end 201,interface circuit (hereafter, referred to as “I/F circuit”) 202, RFcircuit 203, actuator 204, magnetic head 205, servo circuit 206, drivecircuit 207 for actuator, drive circuit 208 for spindle, spindle motor209, and CPU 210.

The CPU 210 is connected with a ROM 211, RAM 212, and timer circuit 213.The ROM 211 is for recording various programs executed at the CPU 210and data required for processing. The RAM 212 is used mainly as a workarea.

The timer circuit 213 is so constructed that it can count times set fromthe information processing unit 100 and form triggers for changing thepower consumption mode. These operations are intended to implement, forexample, the above-mentioned Standby Timer function and the HCAPMfunction described in detail later.

The hard disk 200A is rotationally driven by the spindle motor 209 thatis rotated at a constant speed according to drive signals from the drivecircuit 208 under the control of the CPU 210.

The actuator 204 is controlled according to drive signals from the drivecircuit 207 under the control of the CPU 210 and the servo circuit 206.A swing arm equipped with the magnetic head 205 can be moved in thedirection of the radius of the hard disk 200A by this actuator 204.

The swing arm equipped with the magnetic head 205 is caused to seek to atarget position on the hard disk 200A during accessing; when no accessis made, it is positioned in a area out of the hard disk 200A, and isbrought into so-called unload state.

In recording, information signals, such as AV data, accepted through theconnection end 201 and the I/F circuit 202, are supplied to the RFcircuit 203. The information signals are converted there into signalsfor recording, and then supplied to the magnetic head 205. As alsomentioned above, the magnetic head 205 is positioned on a target trackon the hard disk 200A by the actuator 204 that operates under thecontrol of the CPU 210 and the servo circuit 206.

The magnetic head 205 applies a magnetic field to the target track onthe hard disk 200A according to the signals for recording from the RFcircuit 203. As a result, the signals for recording, that is,information signals, such as AV data, to be recorded are recorded on thehard disk 200A.

In reproduction, the magnetic head is positioned on a target track onthe hard disk 200A by the actuator 204 that operates under the controlof the CPU 210 and the servo circuit 206. The magnetic head 204 detectschange in the magnetic field from the target track, and converts it intoreproduction RF signals as electrical signals and supplies them to theRF circuit 203.

The RF circuit 203 generates reproduction signals from the reproductionRF signals from the magnetic head 205. Then, it supplies them to theinformation processing unit 100 of the recording and reproducing devicein this embodiment through the I/F circuit 202 and the connection end201. As a result, the reproduction signals can be utilized.

The HDD 200 in this embodiment is provided with several powerconsumption modes as, for example, HDDs for personal computers are. Inthe HDD 200 in this embodiment, six power consumption modes areimplemented by the following method: as described below, the HDD 200 isdivided into five circuit portions, and turn-on/off of power supplied toeach circuit portion is controlled.

More specific description will be given. The HDD 200 in this embodimentis divided into five circuit portions: (1) I/F circuit portioncomprising the I/F circuit 202, (2) spindle portion comprising thespindle motor 209 and the drive circuit 208 for rotationally driving thehard disk 200A, (3) actuator portion comprising the actuator 204 and thedrive circuit 207 that control the swing arm equipped with the magnetichead 205, (4) servo circuit portion comprising the servo circuit 206,and (5) RF circuit portion that comprises the RF circuit 203 andconstitutes a channel circuit portion for read/write.

As illustrated in FIG. 3, the HDD is provided with the following modes:Active mode in which data is being read and written and thus all thecircuit portions, the I/F circuit portion (1), spindle portion (2),actuator portion (3), servo circuit portion (4), and RF circuit portion(5), are enabled; and Low Power Active mode (Performance Idle mode) inwhich only the RF circuit portion (5) is disabled.

Further, the HDD is provided with the following modes: Active Idle modein which the RF circuit portion (5) and the servo circuit portion (4)are disabled; Low Power Idle mode in which the RF circuit portion (5),servo circuit portion (4), and actuator portion (3) are disabled;Standby mode in which the RF circuit portion (5), servo circuit portion(4), actuator portion (3), and spindle portion (2) are disabled; andSleep mode in which the power consumption is reduced to the bare minimumlevel at which only the detection of acces to the HDD itself through theI/F circuit can be carried out. Thus, the HDD is provided with the sixmodes in total.

As illustrated as an example of power consumption at the right end ofFIG. 3, Active mode, listed in the uppermost row, is the mode with thehighest power consumption because data is read or written in this mode.The five circuit portions are turned off one by one as it goes towardthe lowermost row. Sleep mode, listed in the lowermost row, is the modewith the lowest power consumption.

Therefore, the effect of power consumption reduction is more increasedin the mode listed in the lower row in FIG. 3. However, the time ittakes to return to Active mode (transition time) is accordinglylengthened. That is, the reduction of power consumption and quick returnto Active mode are in the so-called trade-off relation.

Conventional HDDs used as auxiliary information storage devices forpersonal computers are usually ranked as items to be constructedseparately from personal computers. For this reason, in conventionalHDDs, the reduction of power consumption is accomplished without delayin operation by the following means: a HDD predicts the pattern ofaccess from a personal computer for itself based on the history ofaccess from the personal computer; and the HDD changes its powerconsumption mode. Thus, the personal computer need not take change ofthe power consumption mode of the HDD into account.

Meanwhile, the recording and reproducing device in this embodimentincorporates the HDD 200. With attention focused on the fact that thehost CPU 120 of the information processing unit 100 grasps the timingwith which access is made to the HDD 200, the following operation isperformed: access to the HDD 200 and change of the power consumptionmode are elaborately controlled on the information processing unit 100side. Thus, further reduction of the power consumption is accomplishedwithout hindering operation.

[Control on Power Consumption Mode Change]

Description will be given to control on change of the power consumptionmode of the HDD 200, made in the recording and reproducing device inthis embodiment, comprising the information processing unit 100 and theHDD 200 as information storing unit as mentioned above. In general, thetransfer rates of HDDs tend to increase year by year. For example, some3.5-inch HDDs have the performance with a transfer rate of over 200Mbps. It is assumed that the transfer rate of the HDD 200 in thisembodiment is also 200 Mbps.

The data rate for information signals (contents), such as AV data, to berecorded and reproduced is, for example, approximately 24 Mbps forhigh-definition signals in the MPEG (Moving Picture Experts Group)scheme, and approximately 10 Mbps for DVDs. These data rates are lowerthan the transfer rates of HDDs by an order of magnitude or so. It isassumed that the data transfer rate of the information processing unit100 in this embodiment is also 10 Mbps.

For this reason, the power consumption can be reduced if the followingmeasures are taken: data is stored to some degree in the buffer 105 ofthe information processing unit 100 as host system, and the HDD 200 isaccessed in a short time, the HDD 200 is kept in a low-power consumptionmode only for the time equivalent to the difference between the transferrate of the HDD 200 and the data rate for information signals, such asAV data.

Description will be given with a concrete example taken. Considerationwill be given to the following case: as mentioned above, the data ratefor information-signals, such as AV data, is 10 Mbps; the transfer rateof the HDD 200 is 200 Mbps; and the storage capacity of the buffer 105of the information processing unit 100 as host system is 10 Mbits.

In this case, the time for which data is stored in the buffer isdetermined as follows:10 Mbit/10 Mbps=1 sec  (1)The time it takes to transfer data from the buffer to the HDD isdetermined as follow:10 Mbit/200 Mbps=0.05 sec  (2)As is apparent from Expression (1) and Expression (2), the time forwhich the HDD 200 is accessed is only 0.05 seconds in one second. Forthe remaining 0.95 seconds, the mode may be caused to transition to alow-power consumption mode.

Such an accessing method that a HDD 200 is accessed only for part of theunit time and a low-power consumption mode is established for theremaining time is generally designated as intermittent access scheme.The recording and reproducing device in this embodiment also uses theintermittent access scheme utilizing the difference between the transferrate (10 Mbps) of the information processing unit 100 for informationsignals, such as AV data, and the transfer rate (200 Mbps) of the HDD200.

How efficiently the overall power consumption can be reduced depends onin how short transition time a low-power consumption mode can beestablished (transition to a low-power consumption mode can be made)when there is no access to the HDD 200.

FIG. 4A and FIG. 4B are drawings for explaining normal access andconventional intermittent access. FIG. 4A illustrates the way normalaccess is made, and FIG. 4B illustrates the way conventionalintermittent access is made.

As illustrated in FIG. 4A, in normal access, data is uniformlytransferred between a host system and an HDD 200 in the unit time. It isassumed that, as mentioned above, the data rate of the informationprocessing unit 100 for information signals, such as AV data, is 10Mbps; the transfer rate of the HDD 200 is 200 Mbps; and the powerconsumption in each power consumption mode is as shown at the right endof FIG. 3. In this case, the power consumption in normal access isapproximately 1868 mW, as indicated by the expression boxed in FIG. 4A.

Meanwhile, in conventional intermittent access, the HDD 200 predicts thepattern of access from the host system for itself, and changes its powerconsumption mode, as illustrated in FIG. 4B. In this case, data istransferred in a lump; therefore, after data transfer, the powerconsumption mode can be lowered by two levels.

In this case, the following measures are taken in conventionalintermittent access, as illustrated in FIG. 4B: after transfer of dataequivalent to the unit data amount transferred per unit time iscompleted, the mode is caused to transition from Active mode to LowPower Active mode. To predict the pattern of access from the host systemhere, a transition time of, for example, 0.2 seconds is provided, andthen the mode is caused to transition from Low Power Active mode toActive Idle mode. The power consumption in this conventionalintermittent access is approximately 1193 mW, as indicated by theexpression boxed in FIG. 4B, and the overall power consumption can besignificantly reduced as compared with normal access.

However, the conventional intermittent access illustrated in FIG. 4Binvolves some waste. There is some time (0.2 seconds in the exampleillustrated in FIG. 4A and FIG. 4B) in Low Power Active mode beforetransition to Active Idle mode. Therefore, the power consumption (0.2sec×1850 mW-0.2 sec×950 mW=180 mW) in Low Power Active mode for thisperiod of 0.2 seconds is wasteful. The recording and reproducing devicein this embodiment is so constructed that this wasteful powerconsumption can be reduced at least when data is transferred between theinformation processing unit 100 and the HDD 200.

FIG. 5 is a drawing for explaining intermittent access in the recordingand reproducing device in this embodiment. The following case will betaken as an example: AV data obtained by shooting with the camera block101 is recorded on the hard disk 200A in the HDD 200. The host CPU 120grasps that, after transfer of data equivalent to the unit data amount(10 Mbits) to be transferred in unit time (one second) is completed, ittakes 0.95 seconds for the unit data amount of data to be transferrednext to be stored in the buffer 105. In the above case, therefore, thehost CPU 120 sends out to the HDD 200 an instruction to immediatelytransition to Active Idle mode.

When the HDD 200 receives the instruction to immediately transition toActive mode from the information processing unit 100, it operates toimmediately transition from Active mode to Active Idle mode, asillustrated in FIG. 5. It does not transition to Low Power Active mode.

In conventional intermittent access, the pattern of access from the hostsystem is predicted on the HDD side; therefore, a relatively longtransition time is taken. The above-mentioned constitution eliminatesthis relatively long transition time and accomplishes quick transitionto a target power consumption mode, and thereby reduces the powerconsumption.

In this case, the mode transition time of 0.2 seconds illustrated inFIG. 4B is eliminated. Therefore, the power consumption is reduced to1013 mW, as indicated by the expression boxed in FIG. 5, and the powerconsumption can be further reduced by 180 mW than in the conventionalintermittent mode illustrated in FIG. 4B. As mentioned above, the powerconsumption mode of the HDD 200 is controlled from the informationprocessing unit 100 as host system. The function of making this controlpossible is designated as DPM (Direct Power Management) function in thisspecification.

In this case, to which power consumption mode the present mode should becaused to transition is determined by the information processing unit100 as host system. Therefore, for example, the following problem can besolved: access is made from the information processing unit 100;however, the mode has transitioned to a mode with needlessly low powerconsumption because of the operating state; therefore, it takes muchtime to transition to Active mode.

To make it possible to elaborately and appropriately control change ofthe power consumption mode from the information processing unit 100, asmentioned above, the following measures are taken: the informationprocessing unit 100 is so constructed that it can detect the presentpower consumption mode of the HDD 200.

There is the possibility, though not great, that the host CPU 120 of theinformation processing unit 100 spends much time in, for example,control with respect to various circuit blocks; and it cannot send aninstruction to change the power consumption mode out to the HDD 200 withproper timing. In consideration of this possibility, the powerconsumption mode with high power consumption is prevented from beingmaintained despite the absence of access from the information processingunit 100 by the taking the following measures: the maximum waiting timeis set on the HDD 200 from the information processing unit 100 in caseof transition from each power consumption mode to a mode with lowerpower consumption.

As mentioned above, the maximum waiting time is set from the informationprocessing unit 100 in case of transition from each power consumptionmode to a mode with lower power consumption. The function of utilizingthis is designated as HCAPM (Host Controlled Advanced Power Management)function in this specification.

As also mentioned above, the recording and reproducing device in thisembodiment is so constructed that the following is implemented: when anexternal digital device, such as a personal computer, is connected withthe digital input/output terminal io based on the USB standard, therecording and reproducing device can be used also as an auxiliaryinformation storage device for the external digital device. Therefore,the recording and reproducing device is so constructed that thefollowing is implemented: the conventional APM function, wherein thepattern of access from an external digital device is predicted on theHDD 200 side and the HDD 200 changes its power consumption mode foritself, can also be used; and conventional intermittent access can alsobe made.

The conventional HDDs are provided with the Standby Timer function. Thisis for implementing the following: when there is no access for apredetermined time or longer in so-called Idle mode, the mode is causedto transition to Standby mode. The HDD 200 of the recording andreproducing device in this embodiment is also provided with the StandbyTimer function.

The recording and reproducing device in this embodiment is soconstructed that the host CPU 120 of its information processing unit 100can give various instructions to the HDD 200. Such instructions include:instruction to select which to use, the DPM function or the APMfunction; instruction, given when the DPM function is used, whichspecifies to which power consumption mode the present mode should bechanged; and the like.

In this case, the information processing unit 100 forms a command in apredetermined format at its host CPU 120, and supplies it to the HDD 200through the media controller 106. The HDD 200 is so constructed that thefollowing can be implemented: it accepts commands from the informationprocessing unit 100 through the connection end 201 and the I/F circuit202, and supplies them to the CPU 210; the CPU 210 of the HDD 200performs processing according to commands from the informationprocessing unit 100.

In the recording and reproducing device in this embodiment, theinformation processing unit 100 and the HDD 200 are connected with eachother through an interface based on the ATA standard, for example.Description will be given to concrete examples in this case in which theabove-mentioned functions are carried out. The details of commands thatcan be used in interfaces based on the ATA standard is announced at theweb site at the URL of (http://www.t10.org/).

[Detailed Description of DPM (Direct Power-Management) Function]

Description will be given to the details of the DPM function. Asmentioned above, the information processing unit 100 as host system hasthe best knowledge of the pattern of access to the HDD 200. Based onthis fact, the DPM function is for accomplishing reduction of powerconsumption without depending on the estimation of the pattern of accessfrom the information processing unit 100 by the HDD 200. The DPMfunction is such that the information processing unit 100 elaboratelycontrols the power consumption mode of the HDD 200 for power consumptionreduction.

More specific description will be given. The information processing unit100 carries out various controls on the HDD 200. For example, it recordsdata in the HDD 200, reads data from the HDD 200, supplies variouscommands, and refres to the values on the registers of the HDD. Based onthe state of control of the information processing unit 100 on the HDD200, the information processing unit 100 controls the power consumptionmode of the HDD 200.

In the recording and reproducing device in this embodiment, the DPMfunction is disabled immediately after the power is turned on. When theDPM function is enabled by, for example, the extended Set Featurescommand, the DPM commands become available. That is, immediately afterthe power is turned on, the conventional APM function is used in the HDD200. When the information processing unit 100 instructs the HDD 200 tocarry out the DPM function, using a predetermined command, the DPMfunction is enabled in the HDD 200.

[Instruction Command to Enable/Disable DPM Function]

Description will be given to commands for instructing the HDD 200 toenable/disable the DPM function. As also mentioned above, theinformation processing unit 100 and the HDD 200 are connected with eachother using an interface based on the ATA standard. Therefore, the SetFeatures command laid down in the ATA standard is extended here, andenabling/disabling of the DPM is controlled by the SubCommand Code forthe Features register under this extended Set Features command.

FIG. 6 is a drawing for explaining the format of the Set Featurescommand, and FIG. 7 is a drawing for explaining the values settable onthe Features register under the Set Features command and the meaning ofthem.

As illustrated in FIG. 6, the Set Features command is so constructedthat target values are set in seven registers, each in eight bits (onebyte), provided for the HDD 200; and various instructions are therebygiven from the information processing unit 100 to the HDD 200.

The seven registers available in the HDD 200 when the Set Featurescommand is used are as illustrated in FIG. 6. The registers includeFeatures register, Sector Count register, Sector Number register,Cylinder Low register, Cylinder High register, Device/Head register, andCommand register.

The Features register is loaded with information indicating the contentsof instructions from the information processing unit 100 to the HDD 200.The Sector Count register, Sector Number register, Cylinder Lowregister, and Cylinder High register are used for setting, for example,a time limit and for other purposes.

In the Device/Head register, information that identifies a device to beused is set. More specific description will be given. The ATA standardlays down that two devices, master device and slave device, can beconnected with one bus. In the Device/Head register, informationindicating to which device the command should be directed is set.

In the recording and reproducing device in this embodiment, theinformation processing unit 100 is connected with only one HDD 200.Therefore, 0 (zero) is set in the device indication bit, the fourth bitfrom the MSB (Most Significant Bit) of the Device/Head register.

The Command register is for setting information indicating what commandset the relevant command set is. In this case, “EFh” (h indicateshexadecimal notation), which is a value indicating that the relevantcommand set is the Set Features command, is set.

In this specification, “h” immediately following uppercase alphabeticcharacters A to F, such as the above-mentioned “EFh,” and “h”immediately following numeric characters, such as “25h,” indicate thatthe alphabetic or numeric characters immediately preceding them arerepresented in hexadecimal number.

As also mentioned above, whether to enable or disable the DPM functionis instructed by the SubCommand Code in the Features register. Thevalues that can be used as the SubCommand Code for the Features registerare predetermined as illustrated in FIG. 7. As values that can be usedas the SubCommand Code for the Features register, a value giving aninstruction to enable the DPM function and a value giving an instructionto disable the DPM function are determined in advance.

In this example, as illustrated in FIG. 7, “25h” is taken as the valuegiving an instruction to enable the DPM function (Enable Direct PowerManagement), and “A5h” is taken as the value giving an instruction todisable the DPM function (Disable Direct Power Management).

As described later again, “26h” is newly defined as the value giving aninstruction to use the HCAPM function (Set Host Controlled AdvancedPower Management). As mentioned above, the HCAPM function is soconstructed that it can be utilized in the recording and reproducingdevice in this embodiment.

In this embodiment, as mentioned above, the following values areadditionally defined as values that can be utilized as the SubCommandCode for the Features register under the Set Features command: “25h”(Enable Direct Power Management), “A5h” (Disable Direct PowerManagement), and “26h” (Set Host Controlled Advanced Power Management).

To actually control enabling/disabling of the DPM function, as the SetFeatures command, appropriate values are set in the Features register,Device/Head register, and Command register. As a result, the HDD 200 canbe set for enabling or disabling the DPM function.

FIG. 8A and FIG. 8B are drawings for explaining commands instructing toenable and disable the DPM function. FIG. 8A illustrates a command forenabling the DPM function, and FIG. 8B illustrates a command fordisabling the DPM function.

More specific description will be given. As illustrated in FIG. 8A, toenable the DPM function in the HDD 200, the following command issupplied from the information processing unit 100 to the HDD 200: acommand in which the value in the Features register is “25h”; the valuein the Device/Head register is “A0h” as a predetermined value; and thevalue in the Command register is “EFh,” the value indicating the SetFeatures command. When “25h”, “A0h”, and “EFh” in hexadecimal notationare represented in binary, they are “00100101”, “10100000”, and“11101111,” respectively, as illustrated in FIG. 8A.

As illustrated in FIG. 8B, to disable the DPM function in the HDD 200,the following command is supplied from the information processing unit100 to the HDD 200: a command in which the value in the Featuresregister is “A5h”; the value in the Device/Head register is “A0h” as apredetermined value; and the value in the Command register is “EFh,” thevalue indicating the Set Features command. When “A5h” in hexadecimalnotation is represented in binary, it is “10100101” as illustrated inFIG. 8B.

Thus, the DPM function can be enabled or disabled in the HDD 200 byvarying the value in the Features register using the Set Featurescommand.

[Commands to Instruct Power Consumption Mode with DPM Function Enabled]

An instruction to change the power consumption mode is given from theinformation processing unit 100 to the HDD 200 as follows: the IdleImmediate command laid down in the ATA standard is extended, and theinstruction is given by the value in the Features register under thisextended Idle Immediate command.

FIG. 9 is a drawing for explaining the format of the Idle Immediatecommand, and FIG. 10 is a drawing for explaining the numeric values thatcan be set in the Features register under the Idle Immediate command andthe meaning of them.

As illustrated in FIG. 9, the extended Idle Immediate command is alsoused, similarly with the above-mentioned extended Set Features command,as follows: target values are set in seven registers, each in eight bits(one byte), provided for the HDD 200; and various instructions arethereby given from the information processing unit 100 to the HDD 200.

The seven registers available in the HDD 200 when the Idle Immediatecommand is used are as illustrated in FIG. 9. The registers includeFeatures register, Sector Count register, Sector Number register,Cylinder Low register, Cylinder High register, Device/Head register, andCommand register. The functions of each register are the same as underthe above-mentioned Set Features command.

To which power consumption mode the present mode should be caused totransition is instructed by the value in the Features register under theIdle Immediate command. The values to be set in the Features registerunder the Idle Immediate command are predetermined as illustrated inFIG. 10.

More specific description will be given. In this embodiment, asillustrated in FIG. 10, “00h” is taken as the value giving aninstruction to immediately transition to Active mode (Active Immediate),and “01h” is taken as the value giving an instruction to immediatelytransition to Low Power Active mode (Low Power Active Immediate).

As further illustrated in FIG. 10, “02h” is taken as the value giving aninstruction to immediately transition to Active Idle mode (Active IdleImmediate), and “03h” is taken as the value giving an instruction toimmediately transition to Low Power Idle Immediate mode (Low Power IdleImmediate).

The information processing unit 100 sets any of the values “00h” to“03h,” illustrated in FIG. 10, in the Features register under the IdleImmediate command. It can thereby cause the power consumption mode ofthe HDD 200 to immediately transition to a target power consumptionmode.

Under the Idle Immediate command, “A0h” as a predetermined value is setin the Device/Head register as under the above-mentioned Set Featurescommand, and “E1h” indicating the Idle Immediate command is set in theCommand register.

FIG. 11A to FIG. 11D are drawings for explaining concrete examples ofinstruction commands for instructing to change the power consumptionmode. FIG. 11A illustrates a command instructing immediate transition toActive mode (Active Immediate), and FIG. 11B illustrates a commandinstructing immediate transition to Low Power Active mode (Low PowerActive Immediate).

FIG. 11C illustrates a command instructing immediate transition toActive Idle mode (Active Idle Immediate), and FIG. 11D illustrates acommand instructing immediate transition to Low Power Idle Immediatemode (Low Power Idle Immediate).

Under any of the Idle Immediate commands illustrated in the FIG. 11A toFIG. 11D, the value in the Device/Head register is “A0h,” apredetermined value, and the value in the Command register is “E1h” thatindicates that the relevant command is the Idle Immediate command.

The value in the Features register that indicates to which powerconsumption mode the present mode should be caused to transition is anyof “00h” to “03h” that are values indicating target power consumptionmodes, as illustrated in FIG. 11A to FIG. 11D.

As mentioned above, after the DPM function is enabled in the HDD 200according to an instruction (by the Set Features command) from theinformation processing unit 100, the following operation can beperformed: the HDD 200 can be caused to immediately transition to atarget power consumption mode by an instruction by the Idle Immediatecommand from the information processing unit 100.

Therefore, after the unit data amount of data to be transferred in theunit time is sent out, as illustrated in FIG. 5, the following operationcan be performed: the information processing unit 100 issues the IdleImmediate command illustrated in FIG. 1C, and the power consumption modeof the HDD 200 is thereby caused to immediately transition from Activemode to Active Idle mode.

The HDD 200 is so constructed that the following is implemented: when itreceives the above-mentioned Idle Immediate command from the informationprocessing unit 100, it quickly transitions to the specified powerconsumption mode. In addition, the HDD 200 is so constructed that, whenthe DPM function is disabled, the value in the Features register underthe Idle Immediate command is disregarded.

[Command to Acquire Power Consumption Mode of HDD]

To elaborately control the power consumption mode of the HDD 200 fromthe information processing unit 100 by the above-mentioned DPM function,the information processing unit 100 must accurately grasp the state ofthe HDD 200.

Consequently, the recording and reproducing device in this embodiment isso constructed that the following is implemented: as conventionallypracticed, the HDD 200 is caused to set the status of its powerconsumption mode in the Sector Count register by the Check Power Modecommand, laid down in the ATA standard.

However, the Check Power Mode command is extended here so that the powerconsumption mode of the HDD 200 can be grasped in more detail. Theinformation processing unit 100 is so constructed that the following isimplemented: it refers to the value in the Sector Count register for theHDD 200 at the time of issuance of the Check Power Mode command, and itcan thereby grasp the power consumption mode of the HDD 200 at thattime.

FIG. 12A and FIG. 12B are drawings for explaining the format of theCheck Power Mode command. The command illustrated in FIG. 12A is aninput command from the information processing unit 100 as host system tothe HDD 200; the command illustrated in FIG. 12B is an output commandfrom the HDD 200 to the information processing unit 100.

As illustrated in FIG. 12A, the extended Check Power Mode command isalso used, similarly with the above-mentioned extended Set Featurescommand and extended Idle Immediate command, as follows: target valuesare set in seven registers, each in eight bits (one byte), provided forthe HDD 200; and various instructions are thereby given from theinformation processing unit 100 to the HDD 200.

The seven registers available in the HDD 200 when the Check Power Modecommand is used are as illustrated in FIG. 12A. The registers includeFeatures register, Sector Count register, Sector Number register,Cylinder Low register, Cylinder High register, Device/Head register, andCommand register. The functions of each register are the same as underthe above-mentioned Set Features command and Idle Immediate command.

When the information processing unit 100 makes an attempt to grasp thepresent power consumption mode of the HDD 200, it issues the Check PowerMode command to the HDD 200. Under this command, “A0h,” a predeterminedvalue, is taken as the value in the Device/Head register, as under theSet Features command or Idle Immediate command; and “E5h” that is thevalue indicating the Check Power Mode command is taken as the value inthe Command register.

When the HDD 200 accepts the Check Power Mode command from theinformation processing unit 100, it sets a value indicating its powerconsumption mode in a register for Check Power Mode command output, asillustrate in FIG. 12B. Thus, the information processing unit 100 canrefer to it.

More specific description will be given. As illustrated in FIG. 12B, theregisters for Check Power Mode command output include: Error register,Sector Count register, Sector Number register, Cylinder Low register,Cylinder High register, Device/Head register, and Status register. Thevalue indicating the power consumption mode is set in the Sector Countregister of these registers.

FIG. 13A and FIG. 13B are drawings for explaining examples of values setin the Sector Count register for Check Power Mode command output inorder to provide a notification of the power consumption mode of the HDD200. FIG. 13A illustrates the values used to provide a notification ofthe power consumption mode when the DPM function is disabled. FIG. 13Billustrates the values used to provide a more detailed notification ofthe power consumption mode when the DPM function is enabled.

When the conventional APM function is used, control to change the powerconsumption mode is carried out on the HDD 200 side. Therefore, theinformation processing unit 100 only has to be roughly notified of thepower consumption mode. For this reason, when the DPM function isdisabled and the APM function is used, such a constitution that threestatuses can be notified, as illustrated in FIG. 13A, is adopted. Thethree statuses are Standby mode indicated by “00h,” Idle mode indicatedby “80h,” and Active mode or Idle mode indicated by “FFh.”

In this case, Idle mode is a generic name for three modes, Low PowerActive mode, also referred to as Performance Idle, Active Idle mode, andLow Power Idle mode, as illustrated in FIG. 3. When the powerconsumption mode is any of these three modes, that mode is classifiedunder Idle mode.

Meanwhile, when the DPM function is enabled, the state must be graspedin more detail. Therefore, (1) “FFh” is taken for Active mode, (2) “83h”is taken for Low Power Active mode, (3) “82h” is taken for Active Idlemode, (4) “81h” is taken for Low Power Idle mode, and (5) “00h” is takenfor Standby mode, as illustrated in FIG. 13B. Thus, of the six modesillustrated in FIG. 3, all the power consumption mode, other than Sleepmode in which only the bare minimum power is supplied, can be notifiedof.

As mentioned above, when the DPM function is enabled, the powerconsumption mode of the HDD 200 can be grasped in detail, unlike thecases where the APM function is used. In these cases, the powerconsumption mode is roughly grasped, as illustrated in FIG. 13A. WhenDPM function is enabled, mode changes can be elaborately instructed, forexample, between Low Power Active mode and Active Idle mode and betweenActive Idle mode and Low Power Idle mode.

[HCAPM Function]

As mentioned above, when the DPM function is enabled, the HDD 200 iscaused to follow instructions from the information processing unit 100as host system; the HDD 200 is prevented from changing its powerconsumption mode for itself. However, even if power consumption controlis carried out with the DPM function enabled, as also mentioned above,problems can arise due to some trouble in the information processingunit 100. For example, the information processing unit may not becapable of controlling the power consumption mode of the HDD 200, or itmay take much time to control the power consumption mode.

In this case, the power consumption cannot be reliably reduced if theHDD 200 does not change its power consumption mode until someinstruction is given from the information processing unit 100. The HCAPMfunction is used to cope with this. The HCAPM function is such that: amaximum value (maximum time) is preset on the HDD 200 from theinformation processing unit 100; this maximum value indicates how longthe HDD should wait for access from the information processing unit 100before it can transition to another power consumption mode; based onthis maximum value, the HDD 200 changes its power consumption mode foritself. The recording and reproducing device in this embodiment uses aconventional Standby Timer together.

As mentioned above, the HCAPM function is a function that can be enabledonly when the DPM function is enabled, and it can be said that the HCAPMfunction complements the DPM function. More specific description will begiven. As described with reference to FIG. 6, FIG. 7, and FIG. 8A, theHCAPM function is carried out as follows: only when the DPM function isenabled by the extended Set Features command, it is enabled insynchronization therewith. It is not used together with the conventionalAPM function.

The HCAPM function is used as follows: when the HDD 200 is in Activemode as illustrated in FIG. 14, for example, the transition time T1 fromActive mode to Low Power Active mode is preset on the HDD 200 from theinformation processing unit 100. The transition time T1 is used as acriterion for determining how long the HDD 200 should waits for accessfrom the information processing unit 100 before it can transition to LowPower Active mode for itself.

Similarly, the transition time T2 from Low Power Active mode to ActiveIdle mode is preset on the HDD 200 from the information processing unit100. The transition time T2 is used as a criterion for determining howlong the HDD 200 in Low Power Active mode should wait for access fromthe information processing unit 100 before it can transition to ActiveIdle mode for itself.

Similarly, the transition time T3 from Active Idle mode to Low PowerIdle mode is preset on the HDD 200 from the information processing unit100. The transition time T3 is used as a criterion for determining howlong the HDD 200 in Active Idle mode should wait for access from theinformation processing unit 100 before it can transition to Low PowerIdle mode for itself.

Similarly, the transition time T4 from Low Power Idle mode to Standbymode is preset on the HDD 200 from the information processing unit 100.The transition time T4 is used as a criterion for determining how longthe HDD 200 in Low Power Idle mode should wait for access from theinformation processing unit 100 before it can transition to Standby modefor itself.

FIG. 14 illustrates the foregoing. As illustrated in the drawing, thetransition times T1, T2, T3, and T4 are used as criteria for determiningwhen each power consumption mode should be caused to transition to theone-step lower power consumption mode. These transition times aresupplied in advance from the information processing unit 100 to the HDD200, and set on, for example, the timer circuit 213. The HDD 200 isprevented from varying these settings of transition time.

In the example illustrated in FIG. 14, the transition times T1, T2, T3,and T4 are substantially identical in length; however, the presentinvention is not limited to this. As described later again, thetransition times T1, T2, T3, and T4 may be made different from oneanother, needless to add.

When the DPM function is enabled, the power consumption control iscarried out by the DPM function. As mentioned above, a value obtained byadding a little something extra to the transition time intervals in theDPM function is preset on the HDD 200 by the HCAPM function. Thus,increase in power consumption can be avoided if the informationprocessing unit 100 cannot control the power consumption mode of the HDD200 or it takes much time to control it. This is accomplished by thefollowing operation: with reference to the above-mentioned transitiontimes T1, T2, T3, and T4, the CPU 210 of the HDD 200 causes the HDD tochange its power consumption mode for itself, in cooperation with thetimer circuit 213.

As mentioned above, the transition times T1, T2, T3, and T4 from eachpower consumption mode to the one-step lower power consumption mode arepreset on the HDD 200 as a drive from the information processing unit100 as host system. The setting of these transition times is made bydefining the SubCommand Code for the Features register under theextended Set Features command and the SubCommand Code Specific for theSector Count register and the Sector Number register.

FIG. 15, FIG. 16, and FIG. 17 are drawings for explaining the extendedSet Features command used when the transition times T1, T2, T3, and T4are set for transition from each power consumption mode to the one-steplower power consumption mode.

FIG. 15 is a drawing for explaining the extended Set Features commandused when the transition times T1, T2, T3, and T4 are set for transitionfrom each power consumption mode to the one-step lower power consumptionmode. In FIG. 15, the details of the Device/Head register and theCommand register are the same as those of the extended Set Featurescommand used to instruct to enable/disable the DPM function, describedwith reference to FIG. 6. That is, a value “10100000” (A0h) is set inthe Device/Head register, and a value “11101111” (EFh) that indicatesthe Set Features command is set in the Command register.

A value “26h,” which indicates an instruction to set the transition timeused in the HCAPM function, is set in the Features register, asillustrated in FIG. 7. Information indicating the transition from whatpower consumption mode to what power consumption mode the setting of thetransition time is for is set in the Sector Count register. Therecording and reproducing device in this embodiment is so constructedthat which transition time the setting is for can be specified by “00h,”“01h,” “02h,” or “03h,” as illustrated in FIG. 16.

The actual setting of transition time is made using the SubCommand CodeSpecific for the Sector Number register. The Sector Number register isalso an eight-bit register. In this embodiment, therefore, times from 0msec to 10000 msec are represented in 256 steps that can be representedusing eight bits.

For this reason, the time per step is approximately 40 msec, and in theHDD 200, the actual transition time instructed can be obtained bymultiplying the value in the Sector Number register by 40 msec. Aconcrete example will be taken. When 3 sec is specified for transitiontime, the value in the Sector Number register is 75 steps, “01001011”when represented in binary and “4Bh” when represented in hexadecimal.Thus, 75 steps×40 msec=3000 msec=3 sec.

Thus, the following advantage is brought by using the HCAPM function:even if with the DPM function enabled, the information processing unit100 cannot issue an instruction to change the power consumption mode tothe HDD 200 for some reason, increase in power consumption will notresult.

As also mentioned above, the recording and reproducing device in thisembodiment uses the Standby Timer function as well. Therefore, even ifthe HCAPM function cannot be enabled for some reason, the Standby Timerfunction is available, and increase in power consumption can besuppressed.

As mentioned above, the recording and reproducing device in thisembodiment is provided with the DPM function and the HCAPM function inaddition to the APM function and the Standby Timer function that areconventionally used in power consumption control. The recording andreproducing device is so constructed that the information processingunit 100 can grasp in detail in what power consumption mode the HDD 200is. As a result, the information processing unit 100 can elaboratelycontrol the power consumption mode of the HDD 200, and efficientlyreduce the power consumption.

FIG. 18 is a list of the power consumption control functions used in therecording and reproducing device in this embodiment. The Standby Timerfunction and the APM (Advanced Power Management) function, indicated inthe diagonally shaded areas in FIG. 18, are functions conventionallyprovided in HDDs for personal computers. The DPM (Direct PowerManagement) function and the HCAPM (Host Controlled Advanced PowerManagement) function are extended according to the present invention.

As shown in the upper half of FIG. 18, except the item names, therecording and reproducing device in this embodiment is so constructedthat, when the DPM function is disabled, the Standby Timer functionand/or the APM function can be set to enabled or disabled.

The Standby Timer function is disabled by default, but it can be enabledregardless of the DPM function by setting it again. The APM function isenabled by default, but it can be disabled by setting it again. When theAPM function is disabled, the minimum power consumption control iscarried out; therefore, the APM function of so-called mode zero iscarried out. When the APM function is enabled, the DPM function and theHCAPM function are prevented from being used together.

As shown in the lower half of FIG. 18, except the item names, therecording and reproducing device in this embodiment is so constructedthat, when the DPM function is enabled, the Standby Timer function canbe set to enabled or disabled; however, the APM function is invariablydisabled. As mentioned above, when the DPM function is enabled, theHCAPM function is also enabled in synchronization therewith. Inaddition, the Standby Timer function can be used together.

Next, description will be given to power consumption control in therecording and reproducing device in this embodiment with reference tothe flowchart in FIG. 19. As also mentioned above, the recording andreproducing device in this embodiment is provided with the conventionalAPM function and the DPM function. When these functions aresimultaneously used, proper power consumption control is infeasible.Therefore, it is so constructed that the APM function and the newlyprovided DPM function can be alternatively used.

The conventional Standby Timer function can be used together both withthe APM function and with the DPM function. When the DPM function isused, the HCAPM function can also be used. Basically, the APM functionand the DPM function are alternated as illustrated in the flowchart inFIG. 19.

FIG. 19 is a flowchart for explaining the power consumption controlcarried out when the power is turned on to the recording and reproducingdevice in this embodiment. When the power is turned on to the recordingand reproducing device in this embodiment, the HDD 200 enables the APMfunction first so that power consumption control is carried out by theAPM function (Step S101).

It is determined whether a command to enable the DPM function has beenissued from the information processing unit 100 (Step S102). The HDD 200performs the following operation until a command enabling the DPMfunction is issued from the information processing unit 100: by theconventional APM function, the HDD 200 estimates the pattern of accessfrom the information processing unit 100 and changes its powerconsumption mode for itself.

When the judgment at Step S102 reveals that a command enabling the DPMfunction has been issued from the information processing unit 100, theHDD 200 enables the DPM function and the HCAPM function, and preventsthe APM function from being carried out (Step S103).

Then, it is determined whether a command disabling the DPM function hasbeen issued from the information processing unit 100 (Step S104). TheHDD 200 carries out the following power consumption control until acommand disabling the DPM function is issued from the informationprocessing unit 100: by the newly provided DPM function, the HDD changesits power consumption mode according to the extended Set Featurescommand from the information processing unit 100.

When the DPM function is enabled, the HCAPM function is also enabled.Thus, the following operation can be performed if a command to changethe power consumption mode, which should be otherwise issued from theinformation processing unit 100, is not issued for some reason and thereis no access from the information processing unit 100 for apredetermined period of time: the HDD 200 transitions to a powerconsumption mode with lower power consumption using its own judgment.

If the judgment at Step S104 reveals that a command disabling the DPMfunction has been issued from the information processing unit 100, theHDD 200 disables the DPM function and the HCAPM function (Step S105),and repeats the processing of Step S101 and the following steps.

As also mentioned above, the Standby Timer function can be used togetherwith the conventional APM function and with the new DPM function.Therefore, the recording and reproducing device in this embodiment is soconstructed that the Standby Timer function can be used together withthe APM function or the DPM function according to the user'sinstruction.

Next, description will be given to the operation performed in therecording and reproducing device in this embodiment when the informationprocessing unit 100 grasps the state of the power consumption mode ofthe HDD 200. This processing is not processing in which the informationprocessing unit 100 only issues a command to the HDD 200, for example,an instruction to enable/disable the DPM function, and the setting oftransition time for the HCAPM function.

The above-mentioned processing is so constructed that, when theinformation processing unit 100 grasps the state of the powerconsumption mode of the HDD 200, that is accomplished as describedbelow: the HDD 200 grasps the state of its own power consumption foritself, and the information processing unit 100 refers to it.

FIG. 20 is a flowchart for explaining the operation performed when theinformation processing unit 100 grasps the state of the powerconsumption mode of the HDD 200. There are cases where the host CPU 120of the information processing unit 100 desires to grasp the presentpower consumption mode of the HDD 200 before issuing, for example, acommand to change the power consumption mode.

In such a case, the host CPU 120 of the information processing unit 100performs the processing illustrated in FIG. 20. First, it issues theCheck Power Mode command (Step S201). The Check Power Mode command fromthe information processing unit 100 is accepted by the HDD 200 (StepS202). When the HDD 200 accepts the Check Power Mode command from theinformation processing unit 100, the CPU 210 of the HDD 200 determineswhether the DPM function is presently enabled (Step S203).

In other words, this judgment at Step S203 is processing to determinewhich function is enabled, the DPM function or the APM function. If thejudgment at Step S203 reveals that the DPM function has been enabled,the HDD 200 performs the following operation: it takes as a return valuesuch a value that information indicating the present power consumptionmode can be imparted at such a detailed level as illustrated in FIG.13B. Then, the HDD sets this return value in the Sector Count registerunder the Check Power Mode (Step S204).

If the judgment at Step S203 reveals that the DPM function is disabledand the APM function is enabled, the HDD 200 performs the followingoperation: it takes a return value such a value that informationindicating the present power consumption mode can be imparted at such arough level as illustrated in FIG. 13A. Then, the HDD sets this returnvalue in the Sector Count register under the Check Power Mode (StepS205).

The information processing unit 100 refers to the return value in theSector Count register of the HDD 200. As a result, it can grasp thepresent power consumption mode of the HDD 200 at the level correspondingto the presently enabled power consumption control function (Step S206).

Thus, the recording and reproducing device in this embodiment is soconstructed that the following operation is performed: the host CPU 120of the information processing unit 100 forms various commands, forexample, a command to change the power consumption mode of the HDD 200,according to the state of its own access to (control on) the HDD 200. Itsupplies these commands to the HDD 200 through the media controller 106.

Further, the recording and reproducing device is so constructed that thefollowing operation is performed: the HDD 200 accepts commands throughthe connection end 201 and the I/F circuit 202, and supplies theaccepted commands to the CPU 210; the CPU 210 of the HDD 200 performsthe following operations according to the accepted commands: controllingthe power supplied to each part; grasping the power consumption mode ofthe HDD itself, and imparting it to the information processing unit 100;and detecting the timing with which the power consumption mode should bechanged, to change the power consumption mode in cooperation with thetimer circuit 213.

As mentioned above, the recording and reproducing device in thisembodiment is so constructed that the information processing unit 100itself elaborately controls the power consumption of the HDD 200 basedon the state of its own access to (the state of control on) the HDD 200;and the power consumption can be thereby reduced.

In the embodiment described above as an example, the recording andreproducing device comprises the information processing unit 100 and theHDD 200. However, the information storing unit need not be a HDD, and itmay be a drive for various disk recording media, including optical diskssuch as DVDs and magneto-optical disks such as MDs.

The information processing unit 100 and the information storing unit 200such as a HDD need not exist in the same enclosure. The presentinvention is applicable to cases where they are formed separately fromeach other and connected with each other thorough a predeterminedinterface cable.

However, in mobile devices such as the above-mentioned digital videocameras in which the information processing unit 100 and the informationstoring unit 200 are housed in one enclosure, the present invention canbe effectively utilized. This is because the power consumption can bemore efficiently reduced, and this brings about various effects,including lengthened battery duration and suppression of temperaturerise in the enclosure.

In the embodiment described above as an example, the informationprocessing unit 100 and the information storing unit 200 are connectedwith each other through an interface based on the ATA standard. Thepresent invention is not limited to this, and various interfaces can beused as the interface that connects the information processing unit andthe information storing unit such as a HDD.

In such a case, therefore, commands corresponding to the variouscommands described with the case where an interface based on the ATAstandard is used taken as an example are formed in correspondence withthe interface used.

In the above-mentioned example, the embodiment is a recording andreproducing device. The present invention is not limited to this, and isapplicable to various types of recording devices and reproducingdevices. That is, the present invention is applicable to cases whereinformation signals are read from a recording medium in a drive such asa HDD and reproduced as well as cases where information signals such asAV data are recorded. In such cases as well, the information processingunit can control the power consumption mode of the drive based on thestate of its own access to the drive.

In the embodiment described above, the conventional APM function and theDPM function according to the present invention are alternatively used.In this case, when the DPM function is enabled, the HCAPM function isalso enabled. However, even if the DPM function is used, the HCAPMfunction may be kept unused.

Therefore, in addition to alternative use of the APM function and theDPM function, the Standby Timer function may be used together, or theHCAPM function may be switched between enabled state and disabled state.

That is, either or both of the DPM function and HCAPM function accordingto the present invention can be selectively used together with either orboth of the conventional APM function and Standby Timer function. Or,only the DPM function or only the DPM function and the HCAPM functioncan be used without use of the APM function or the Standby Timerfunction.

The recording and reproducing device in the above-mentioned embodimentis so constructed that the following takes place: for example, whennormal mode is established and an external device is connected with thedigital input/output terminal io, power can be supplied from theexternal device. Therefore, the APM function is used; even if shootingmode or normal mode is established, the DPM function can be used with noexternal device connected with the digital input/output terminal io.Needless to add, this is just an example. Cases where only the APMfunction can be used and cases where the DPM function can be used may bedefined.

In the recording and reproducing device in the above-mentionedembodiment, the intermittent access scheme is used. Thus, reduction ofpower consumption can be accomplished and further temperature rise inthe enclosure can be suppressed. In addition, the following spillovereffect is brought about: since the time for which the informationstoring unit (storage device portion) such as a HDD is being accessed isshort, the probability of occurrence of glitches due to shock such asdisturbance is accordingly lowered.

According to the present invention, as mentioned above, the powerconsumption of disk drives such as HDDs and DVD drives can beefficiently and reliably reduced. In case of mobile devices or the like,the battery duration can be lengthened, and further the temperature inthe enclosure and the like can be prevented from unnecessarily rising.

FIG. 1:

101/ Camera block

103/ Encoder/decoder

105/ Buffer

106/ Media CTL

107/ Digital I/F

CPU

To host CPU

111/ Key operation portion

120/ Host CPU

123/ Nonvolatile memory

FIG. 2:

202/ I/F circuit

203/ RF circuit

204/ Actuator

206/ Servo circuit

207/ Drive circuit

208/ Drive circuit

209/ Spindle motor

213/ Timer circuit

FIG. 3: Power Save Modes of Information Storage Device

(HDD)

Circuit portion

I/F

I/F circuit

Spindle

Actuator

Servo circuit

RF

RF circuit

Examples of power consumption

Mode

Active

Low Power Active

(Performance Idle)

Active Idle

Low Power Idle

Standby

Sleep

On disk

Out of disk

Read

Write

FIG. 4A:

˜

˜sec

10M

10 Mbits in total

Write

Low Power Active

FIG. 4B:

˜

˜sec

˜M

˜Mbits

Write

Active Idle

Mode transition time

FIG. 5:

˜

˜sec

10M

10 Mbits

Write

Low Power Active

Active Idle

FIG. 6:

Command code

Registers

Features

Sector Count

Sector Number

Cylinder Low

Cylinder High

Device/Head

Command

SubCommand Code

SubCommand Specific

FIG. 7:

Value

Description

FIG. 8A:

SET FEATURES

SET FEATURES Command

Registers

Features

Device/Head

Command

FIG. 8B:

Registers

Features

Device/Head

Command

FIG. 9:

Command code

Registers

Features

Sector Count

Sector Number

Cylinder Low

Cylinder High

Device/Head

Command

FIG. 10:

Value

Description

FIG. 11A:

IDLE IMMEDIATE

IDLE IMMEDIATE Command

Registers

Features

Device/Head

Command

FIG. 11B:

Registers

Features

Device/Head

Command

FIG. 11C:

Registers

Features

Device/Head

Command

FIG. 11D:

Registers

Features

Device/Head

Command

FIG. 12A:

Command code

Registers

Features

Sector Count

Sector Number

Cylinder Low

Cylinder High

Device/Head

Command

FIG. 12B:

Registers

Error

Sector Count

Sector Number

Cylinder Low

Cylinder High

Device/Head

Status

FIG. 13A:

Value

Description

Standby mode

Idle mode

Active mode or Idle mode.

FIG. 13B:

Value

Description

Active mode

Low Power Active mode

Active Idle mode

Low Power Idle mode

Standby mode

FIG. 14:

Active

Low Power Active

Active Idle

Low Power Idle

Standby

Sleep

˜ Transition time ˜

FIG. 15:

Command code

Registers

Features

Sector Count

Sector Number

Cylinder Low

Cylinder High

Device/Head

Command

FIG. 16:

Sector Count

Definition of Sector Count

Value

Description

00h/ Specify transition time from Active to Low Power Active

01h/ Specify transition time from Low Power Active to Active Idle

02h/ Specify transition time from Active Idle to Lower Power Idle

03h/ Specify transition time from Lower Power Idle to Standby

FIG. 17:

Value in Sector Number register×40 msec=Set time - - - (1)

FIG. 18:

List of Power Consumption Control Functions

Setting

Setting of Direct Power Management

Setting of Standby Timer

PC

Setting of Advanced Power Management for PC

Operation

Standby Timer

PC

Advanced Power Management for PC

Host Controlled Advanced Power Management

Direct Power Management

Disabled

Enabled

FIG. 19:

Start

S101/ Control power consumption mode by APM function

S102/ Enabling DPM function instructed?

S103/ Enable DPM function and HCAPM function, and stop APM function

S104/ Disabling DPM function instructed?

S105/ Disable DPM function and HCAPM function

FIG. 20:

Start

S201/ Issue Check Power Mode command from information processing unit

S202/ Accept Check Power Mode command at HDD

S203/ DPM function enabled?

S204/ Set power consumption mode as return value for Check Power Modecommand at detailed level

S205/ Set power consumption mode as return value for Check Power Modecommand at rough level

S206/ Refer to return value at information processing unit

End

1. Information processing equipment comprising: an information storingmeans that records or reproduces data according to a plurality of powerconsumption modes; and an information processing means that controls theinformation storing means with respect to at least recording orreproduction of the data, characterized in that: the informationprocessing means forms command information for changing the powerconsumption mode of the information storing means to a target powerconsumption mode based on the state of control, and the informationstoring means changes the power consumption mode of the informationstoring means based on the command information.
 2. The informationprocessing equipment according to claim 1, characterized in that: theinformation processing means forms instruction information forinstructing whether to change the power consumption mode, and whenchange of the power consumption mode is not instructed by theinstruction information, the information storing means makes a selectionand changes the power consumption mode based on the state of controlfrom the information processing means.
 3. The information processingequipment according to claim 1 or claim 2, characterized in that: whenthe information storing means is not controlled by the informationprocessing means for a predetermined time, the information processingmeans forms time information including the predetermined time for theinformation storing means to change the power consumption mode foritself, and when the power consumption mode is to be changed based onthe command information from the information processing means and theinformation processing means does not carry out control for thepredetermined time or more, specified by the time information, theinformation storing means changes the power consumption mode for itself.4. The information processing equipment according to claim 1, claim 2,or claim 3, comprising: a camera means that picks up the image of asubject and takes in the image as electrical signals, characterized inthat: when an image is picked up with the camera means, the informationstoring means changes the power consumption mode of the informationstoring means based on the command information.
 5. The informationprocessing equipment according to claim 1, claim 2, claim 3, or claim 4,comprising: an external connection end for an external device to recordor reproduce data to or from the information storing means,characterized in that: when the external device is recording orreproducing the data to or from the storing means through the externalconnection end, the information storing means changes the powerconsumption mode based on the state of control from an external deviceconnected with the external connection end with respect to at leastrecording or reproducing of the data.
 6. A power consumption controlmethod associated with an information storing means, carried out ininformation processing equipment comprising: the information storingmeans that records or reproduces data according to a plurality of powerconsumption modes, and an information processing means that controls theinformation storing means with respect to at least recording orreproducing of the data, characterized in that the method comprises: astep in which the information processing means produces commandinformation for changing the power consumption mode of the informationstoring means to a target power consumption mode based on the state ofcontrol, and a step in which the information storing means changes thepower consumption mode of the information storing means based on thecommand information.
 7. The power consumption control method accordingto claim 6, characterized in that the method comprises: a step in whichthe information processing means forms instruction information forinstructing whether to change the power consumption mode, and a step inwhich when change of the power consumption mode is not instructed by theinstruction information, the information storing means makes a selectionand changes the power consumption mode based on the state of controlfrom the information processing means.
 8. The power consumption controlmethod according to claim 6 or claim 7, characterized in that the methodcomprises: a step in which when the information storing means is notcontrolled by the information processing means for a predetermined time,the information processing means forms time information including thepredetermined time for the information storing means to change the powerconsumption mode for itself, and a step in which when the powerconsumption mode is to be changed based on the command information fromthe information processing means and the information processing meansdoes not carry out control for the predetermined time or more, specifiedby the time information, the information storing means changes the powerconsumption mode for itself.
 9. The power consumption control methodaccording to claim 6, claim 7, or claim 8, comprising: a camera meansthat picks up the image of a subject and takes in the image aselectrical signals, characterized in that: when an image is picked upwith the camera means, the information storing means changes the powerconsumption mode of the information storing means based on the commandinformation.
 10. The power consumption control method according to claim6, claim 7, claim 8, or claim 9, comprising: an external connection endfor an external device to record or reproduce data to or from theinformation storing means, characterized in that: when the externaldevice is recording or reproducing the data to or from the storing meansthrough the external connection end, the information storing meanschanges the power consumption mode based on the state of control from anexternal device connected with the external connection end with respectto at least recording or reproducing of the data.